My laptop is a Celeron 2.4Ghz and in my testing it was a fair bit faster with -march=pentium4. BUT!!! Note that the current GCC code produces bad SSE2 instructions and so Pentium4 should not be used. So use penium3 instead (which has sse support unlike i686).
I think 'current' gcc builds sse2 instructions fine. gcc 3.2.3 I believe was the version that fixed outstanding bugs. As well, 3.3 is fine.
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Chris I
My Bonnie looked into a gas tank, The height of its contents to see! She lit a small match to assist her, Oh, bring back my Bonnie to me.
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